Transcatheter patent ductus arteriosus closure in premature infants requiring high-frequency ventilation.

Transcatheter closure has become a common treatment method for patent ductus arteriosus in premature infants at many centres; however, many remain uncertain about the ability to perform the procedure in the catheterisation laboratory for infants requiring high-frequency ventilation. This study presents our centre's experience following the implementation of neonatal ventilatory guidelines, which resulted in 100% procedural success without any procedural or respiratory adverse events.

Percutaneous device closure of hemodynamically significant coronary fistula following endomyocardial biopsy in a pediatric heart transplant patient.

Coronary artery fistula is a rare but well-documented complication of right ventricular endomyocardial biopsy, particularly in the adult population. Typically, these fistulae never reach clinical or hemodynamic significance, but some may cause coronary steal and ventricular dysfunction. We report a case of a significant coronary artery fistula requiring device closure in the cardiac catheterization laboratory with subsequent improvement of clinical symptoms and cardiac function.

Follow the MAPCA: an unusual source of right pulmonary artery flow.

Major aortopulmonary collateral arteries in the setting of pulmonary atresia with intact ventricular septum are very rarely encountered, having been documented in only a handful of case reports. We present the right ventriculogram of a patient found to have this rare combination of findings along with right ventricular-dependent coronary artery circulation and unusual supply of the right pulmonary artery.

Cutting balloon angioplasty on branch pulmonary artery stenosis in pediatric patients.

OBJECTIVES: To identify medium-term results following cutting balloon angioplasty (CBA) for branch pulmonary artery stenosis (PAS) and predictors of successful intervention. BACKGROUND: CBA has emerged as a successful alternative therapy for PAS resistant to conventional balloon angioplasty techniques but there is little information on medium and long-term outcomes. METHODS: This is a descriptive, single center, retrospective chart review of pediatric patients who underwent CBA for PAS at Arkansas Children's Hospital between May 2005 and December 2020. We reviewed demographics, procedural specifics, and 30-day complications. RESULTS: Forty-four patients underwent pulmonary artery CBA on 114 pulmonary artery segments through 126 catheterization cases, totaling 148 CBA events. Thirty-three individual pulmonary arteries underwent repeat intervention. Average minimal luminal diameter increase from pre-CBA to end of follow-up was 57% (CI, 38%-75%). Absence of Tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries (TOF/PA/MAPCAs) and the absence of Alagille Syndrome, Williams Syndrome, or Arterial Tortuosity Syndrome (ATS) were associated with increased odds of sustained success by 70% (CI, 0.11-0.79) and 91% (CI, 0.02-0.56), respectively. Increasing the cutting balloon diameter-to-minimal luminal diameter ratio by 0.5 increased odds of successful intervention by 2.37-fold (CI, 1.7-3.3). Seven patients had 30-day complications including one death. CONCLUSIONS: In the longest follow-up to date of children and adolescents who underwent CBA for branch PAS, we found that there was moderate medium-term success. Additionally, absence of TOF/PA/MAPCAs, absence of Alagille Syndrome, Williams Syndrome, or ATS, and high cutting balloon diameter-to-minimal luminal diameter ratio are predictors of sustained results.

Post-market surveillance to detect adverse events associated with Melody® valve implantation.

OBJECTIVE: The aim of this study was to describe previously unrecognised or under-recognised adverse events associated with Melody® valve implantation. BACKGROUND: In rare diseases and conditions, it is typically not feasible to conduct large-scale safety trials before drug or device approval. Therefore, post-market surveillance mechanisms are necessary to detect rare but potentially serious adverse events. METHODS: We reviewed the United States Food and Drug Administration's Manufacturer and User Facility Device Experience (MAUDE) database and conducted a structured literature review to evaluate adverse events associated with on- and off-label Melody® valve implantation. Adverse events were compared with those described in the prospective Investigational Device Exemption and Post-Market Approval Melody® transcatheter pulmonary valve trials. RESULTS: We identified 631 adverse events associated with "on-label" Melody® valve implants and 84 adverse events associated with "off-label" implants. The most frequent "on-label" adverse events were similar to those described in the prospective trials including stent fracture (n=210) and endocarditis (n=104). Previously unrecognised or under-recognised adverse events included stent fragment embolisation (n=5), device erosion (n=4), immediate post-implant severe valvar insufficiency (n=2), and late coronary compression (n=2 cases at 5 days and 3 months after implantation). Under-recognised adverse events associated with off-label implantation included early valve failure due to insufficiency when implanted in the tricuspid position (n=7) and embolisation with percutaneous implantation in the mitral position (n=5). CONCLUSION: Post-market passive surveillance does not demonstrate a high frequency of previously unrecognised serious adverse events with "on-label" Melody® valve implantation. Further study is needed to evaluate safety of "off-label" uses.

Alternative repair strategies for ductal-dependent tetralogy of fallot and short-term postoperative outcomes, a multicenter analysis.

Our aim was to evaluate postoperative morbidity and mortality following initial intervention, comparing primary repair versus palliative shunt in the setting of ductal-dependent tetralogy of Fallot. When neonatal surgical intervention is required, controversy and cross-center variability exists with regard to surgical strategy. The multicenter Pediatric Health Information System database was queried to identify patients with TOF and ductal-dependent physiology, excluding pulmonary atresia. Eight hundred forty-five patients were included-349 (41.3%) underwent primary complete repair, while 496 (58.7%) underwent initial palliation. Palliated patients had significantly higher comorbid diagnoses of genetic syndrome and coronary artery anomalies. Primary complete repair patients had significantly increased morbidity across a number of variables compared to shunt palliation, but mortality rate was equal (6%). Second-stage complete repair was analyzed for 285 of palliated patients, with median inter-stage duration of 231 days (175-322 days). In comparison to primary complete repairs, second-stage repairs had significantly decreased morbidity and mortality. However, cumulative morbidity was higher for the staged patients. Median adjusted billed charges were lower for primary complete repair ($363,554) compared to staged repair ($428,109). For ductal-dependent TOF, there is no difference in postoperative mortality following the initial surgery (6%) whether management involves primary repair or palliative shunt. Although delaying complete repair by performing a palliative shunt is associated with a shift of much of the morbidity burden to outside of the newborn period, there is greater total postoperative morbidity and resource utilization associated with the staged approach.

Early detection of cardiac dysfunction by strain and strain rate imaging in children and young adults with marfan syndrome.

OBJECTIVES: Strain and strain rate imaging have been reported to detect cardiac dysfunction more accurately than conventional methods in adults with Marfan syndrome, but their utility has not been proven in younger patients. We sought to determine whether strain and strain rate imaging would allow early detection of cardiac dysfunction in children and young adults with Marfan syndrome. METHODS: Unoperated patients (<30 years) with Marfan syndrome and healthy control participants were prospectively enrolled. Patients with greater than mild mitral or aortic insufficiency were excluded. Left ventricular systolic function was assessed by standard M-mode imaging. The strain and strain rate values were obtained from apical 4-chamber (longitudinal) and parasternal short-axis views at basal and midventricular levels (radial and circumferential). Data from the two groups were compared by a t test. RESULTS: Sixteen patients with Marfan syndrome (mean age ± SD, 14.4 ± 6.4 years; range, 5.8-28.9 years) and 26 controls (mean age, 12.4 + 4.4 year; range, 4.1-18.1 years) were enrolled. Demographics and left ventricular end-diastolic dimensions were similar between the patients with Marfan syndrome and the controls. The M-mode-derived shortening fraction was significantly lower in the patients with Marfan syndrome compared to the controls, even though the values were within normal limits. The patients with Marfan syndrome had lower regional radial and circumferential strain rates, but there were no significant difference in strain between the groups. CONCLUSIONS: Strain rate imaging may be useful in detection of subclinical changes in cardiac function in patients with Marfan syndrome when conventional echocardiographic parameters are within normal limits. These findings may be clinically important and warrant closer follow-up of these patients to monitor for cardiac dysfunction.

Noninvasive estimation of diastolic pulmonary artery pressure by Doppler analysis of tricuspid regurgitation velocity in pediatric patients.

PURPOSE: Diastolic pulmonary artery pressure (dPAP) is equal to right ventricular pressure at the time of pulmonary valve opening. We studied the accuracy of dPAP estimated from Doppler profile of tricuspid regurgitation (TR) jet in pediatric patients. METHODS: Echocardiograms were prospectively performed on consecutive pediatric heart transplant recipients undergoing right-heart catheterization and endomyocardial biopsy. An estimate of dPAP was obtained by superimposing the pulmonary valve opening time, indexed to the electrocardiogram, onto the TR Doppler tracing. Echocardiographic estimates of dPAP from end-diastolic pulmonary regurgitation (PR) were obtained for comparison. Catheter-derived right atrial pressure was added to the Doppler gradient in both groups. Doppler estimates and catheter-derived measurements of dPAP were compared using Lin correlation and Bland-Altman analysis. RESULTS: Sixty-five catheterization studies were performed on 35 patients (20 males): median age at enrollment: 12.1 years (4 months to 18 years); median time: since transplant of 1.2 years (21 days to 16.1 years). Adequate TR signal was obtained in a significantly higher proportion of patients than an adequate PR signal (65% vs. 43%, respectively, P = .007). Median catheter-derived dPAP was 12 mm Hg (6-30 mm Hg) and right atrial pressure was 6 mm Hg (1-17 mm Hg). Median estimated dPAP from TR was 15 mm Hg (range: 7-29 mm Hg), with the Lin correlation coefficient of 0.74 (95% confidence interval [CI]: 0.6-0.87). Median estimate for dPAP from PR was 10 mm Hg (range: 2-25 mm Hg), with the Lin correlation coefficient of 0.74 (95% CI: 0.58-0.9). There was excellent interobserver agreement for dPAP from TR with the Lin correlation coefficient of 0.946 (95% CI: 0.803-0.986). CONCLUSION: Doppler estimation of dPAP from TR is a novel, reliable, noninvasive method and compares favorably with estimation from PR. Adequate TR signal for estimation of dPAP can be obtained more frequently in children than adequate PR signal, thereby increasing the proportion of patients in whom dPAP can be estimated noninvasively.

Aortopulmonary index as a novel morphologic correlate of early recurrence of coarctation of aorta after surgical repair in infancy.

BACKGROUND: The aim of this study was to determine morphologic correlates of early reintervention for recurrent coarctation in infants undergoing surgical repair in the current era. METHODS: Medical records of infants who underwent repair of coarctation were retrospectively reviewed. Z scores for aortic segments, relative aortic arch segmental dimensions (indexed to ascending or descending aortic dimension), and aortopulmonary index (the ratio of aortic to pulmonary annular diameter) were derived from preoperative echocardiograms. RESULTS: Eighty-seven patients underwent repair (median age, 13 days). Early arch reintervention (<1 year after surgery) was performed in 11. Lower aortopulmonary index and Z scores of the aortic annulus and sinotubular junction were associated with early reintervention. Aortopulmonary index < 0.6 was the best correlate (sensitivity, 72.7%; specificity, 73.7%; area under the curve, 0.732). Aortic arch dimensions were not correlated with early reintervention. CONCLUSION: In the current era, aortopulmonary index rather than aortic arch hypoplasia is correlated with the need for reintervention for recurrent coarctation within 1 year of surgery.

Long-term outcomes of intraoperative pulmonary artery stent placement for congenital heart disease.

OBJECTIVE: Our objective was to examine long-term outcomes of intraoperative pulmonary artery stents and determine risk factors for reintervention BACKGROUND: Short-term outcomes of intraoperative pulmonary artery stents have been reported previously. However, long-term results are unknown. METHODS: We conducted a retrospective review of patients who underwent intraoperative pulmonary artery stent placement for branch pulmonary artery stenosis. RESULTS: Ninety-six stents were implanted intraoperatively in 67 patients. Twenty-seven patients received two or more stents at initial intervention. Median patient age at initial stent placement was 1.8 years. Median post-inflation diameter was 8 mm. At a mean follow-up of 7.6±4.5 years, 49% of stents required reintervention (balloon angioplasty at catheterization in 28 patients and surgical revision in 19 patients). Actuarial freedom from reintervention at 2, 5, and 10 years was 68%, 49%, and 40%, respectively. In univariate analysis of time to first reintervention, age at implantation<2 yrs (P<0.0009) and initial post-inflation stent diameter<10 mm (P<0.0002) were associated with risk for reintervention. Multivariable Cox regression analysis showed age<2 years (P<0.005) and diagnosis of tetralogy of Fallot (p<0.002) or truncus arteriosus (P<0.007) to be significant risk factors for reintervention. CONCLUSION: Intraoperative placement of stents in the pulmonary arteries is an alternative to surgical angioplasty, but is associated with a high incidence of reintervention. Age<2 years and the diagnosis of tetralogy of Fallot or truncus arteriosus are risk factors for reintervention.

Sonographic physical diagnosis 101: teaching senior medical students basic ultrasound scanning skills using a compact ultrasound system.

This project was designed to test the feasibility of introducing ultrasound to senior medical students as a primary diagnostic tool in the evaluation of patients. Specifically, its aim was to determine if it is possible for medical students untrained in sonography to gain basic competence in performing abdominal ultrasound with limited didactic and hands-on instructions. Registered sonographers provided the students with hands-on instructions on the use of a compact ultrasound system. They were likewise shown how to evaluate specific organs and perform measurements. The results of the student measurements and those obtained by the sonographers were compared. There was close correlation between the results obtained by sonographers and students on both normal and abnormal findings. This supports the concept that medical students can be taught basic ultrasound skills with limited didactic and hands-on instructions with the potential of using these skills in the patient clinics as an adjunct to routine physical diagnosis.